Relativistic calculations of 3d excitation energies in the rare-earth metals

A systematic investigation of 3d-electron excitation energies in the rare-earth metals is described. The 3d/sub 3/2/ and 3d/sub 5/2/ energy levels are calculated by a method based on the renormalized-atom approach which has proved successful in calculating 4f and 5s level positions in these materials. 3d-4f multiplet effects, which are small compared to the spin-orbit splittings, and satellite structures are not considered. Total energy differences obtained within the approximation of a completely screened final state, in which the atomic cell having a 3d hole is electrically neutral, lead to results in accord with available x-ray photoemission measurements; one-electron values are 20--33 eV larger. The impact of the complete screening assumption is examined by estimating excitation energies corresponding to ionized final states. The presence of a screening electron reduces the 3d binding energy by 4 --5 eV, a value similar to that calculated for the 4f and 5s levels